{"id":1736,"date":"2016-10-09T15:56:01","date_gmt":"2016-10-09T07:56:01","guid":{"rendered":"https:\/\/ai.zhousir.top\/?p=1736"},"modified":"2017-07-15T17:57:49","modified_gmt":"2017-07-15T09:57:49","slug":"hashmap%e7%9a%84%e5%b7%a5%e4%bd%9c%e5%8e%9f%e7%90%86","status":"publish","type":"post","link":"https:\/\/ai.zhousir.top\/?p=1736","title":{"rendered":"HashMap\u7684\u5de5\u4f5c\u539f\u7406"},"content":{"rendered":"<p>\u5148\u6765\u4e9b\u7b80\u5355\u7684\u95ee\u9898<\/p>\n<p><strong>\u201c\u4f60\u7528\u8fc7HashMap\u5417\uff1f\u201d \u201c\u4ec0\u4e48\u662fHashMap\uff1f\u4f60\u4e3a\u4ec0\u4e48\u7528\u5230\u5b83\uff1f\u201d<\/strong><\/p>\n<p>\u51e0\u4e4e\u6bcf\u4e2a\u4eba\u90fd\u4f1a\u56de\u7b54\u201c\u662f\u7684\u201d\uff0c\u7136\u540e\u56de\u7b54HashMap\u7684\u4e00\u4e9b\u7279\u6027\uff0c\u8b6c\u5982<span style=\"color: #993300;\">HashMap\u53ef\u4ee5\u63a5\u53d7null\u952e\u503c\u548c\u503c\uff0c\u800cHashtable\u5219\u4e0d\u80fd<\/span>\uff1b<span style=\"color: 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underline; color: #993300;\">\u91cd\u8981\u77e5\u8bc6\u70b9<\/span>\u7684\u9762\u8bd5\u8005\u4f1a\u8bf4\uff0c<span style=\"color: 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factor)\u5b9a\u4e49\u7684\u5bb9\u91cf\uff0c\u600e\u4e48\u529e\uff1f\u201d<\/strong>\u9664\u975e\u4f60\u771f\u6b63\u77e5\u9053HashMap\u7684\u5de5\u4f5c\u539f\u7406\uff0c\u5426\u5219\u4f60\u5c06\u56de\u7b54\u4e0d\u51fa\u8fd9\u9053\u9898\u3002\u9ed8\u8ba4\u7684\u8d1f\u8f7d\u56e0\u5b50\u5927\u5c0f\u4e3a0.75\uff0c\u4e5f\u5c31\u662f\u8bf4\uff0c\u5f53\u4e00\u4e2amap\u586b\u6ee1\u4e8675%\u7684bucket\u65f6\u5019\uff0c\u548c\u5176\u5b83\u96c6\u5408\u7c7b(\u5982ArrayList\u7b49)\u4e00\u6837\uff0c\u5c06\u4f1a\u521b\u5efa\u539f\u6765HashMap\u5927\u5c0f\u7684\u4e24\u500d\u7684bucket\u6570\u7ec4\uff0c\u6765\u91cd\u65b0\u8c03\u6574map\u7684\u5927\u5c0f\uff0c\u5e76\u5c06\u539f\u6765\u7684\u5bf9\u8c61\u653e\u5165\u65b0\u7684bucket\u6570\u7ec4\u4e2d\u3002\u8fd9\u4e2a\u8fc7\u7a0b\u53eb\u4f5crehashing\uff0c\u56e0\u4e3a\u5b83\u8c03\u7528hash\u65b9\u6cd5\u627e\u5230\u65b0\u7684bucket\u4f4d\u7f6e\u3002<\/p>\n<p>\u5982\u679c\u4f60\u80fd\u591f\u56de\u7b54\u8fd9\u9053\u95ee\u9898\uff0c\u4e0b\u9762\u7684\u95ee\u9898\u6765\u4e86\uff1a<strong>\u201c\u4f60\u4e86\u89e3\u91cd\u65b0\u8c03\u6574HashMap\u5927\u5c0f\u5b58\u5728\u4ec0\u4e48\u95ee\u9898\u5417\uff1f\u201d<\/strong>\u4f60\u53ef\u80fd\u56de\u7b54\u4e0d\u4e0a\u6765\uff0c\u8fd9\u65f6\u9762\u8bd5\u5b98\u4f1a\u63d0\u9192\u4f60\u5f53\u591a\u7ebf\u7a0b\u7684\u60c5\u51b5\u4e0b\uff0c\u53ef\u80fd\u4ea7\u751f\u6761\u4ef6\u7ade\u4e89(race condition)\u3002<\/p>\n<p>\u5f53\u91cd\u65b0\u8c03\u6574HashMap\u5927\u5c0f\u7684\u65f6\u5019\uff0c\u786e\u5b9e\u5b58\u5728\u6761\u4ef6\u7ade\u4e89\uff0c\u56e0\u4e3a\u5982\u679c\u4e24\u4e2a\u7ebf\u7a0b\u90fd\u53d1\u73b0HashMap\u9700\u8981\u91cd\u65b0\u8c03\u6574\u5927\u5c0f\u4e86\uff0c\u5b83\u4eec\u4f1a\u540c\u65f6\u8bd5\u7740\u8c03\u6574\u5927\u5c0f\u3002\u5728\u8c03\u6574\u5927\u5c0f\u7684\u8fc7\u7a0b\u4e2d\uff0c\u5b58\u50a8\u5728\u94fe\u8868\u4e2d\u7684\u5143\u7d20\u7684\u6b21\u5e8f\u4f1a\u53cd\u8fc7\u6765\uff0c\u56e0\u4e3a\u79fb\u52a8\u5230\u65b0\u7684bucket\u4f4d\u7f6e\u7684\u65f6\u5019\uff0cHashMap\u5e76\u4e0d\u4f1a\u5c06\u5143\u7d20\u653e\u5728\u94fe\u8868\u7684\u5c3e\u90e8\uff0c\u800c\u662f\u653e\u5728\u5934\u90e8\uff0c\u8fd9\u662f\u4e3a\u4e86\u907f\u514d\u5c3e\u90e8\u904d\u5386(tail traversing)\u3002\u5982\u679c\u6761\u4ef6\u7ade\u4e89\u53d1\u751f\u4e86\uff0c\u90a3\u4e48\u5c31\u6b7b\u5faa\u73af\u4e86\u3002\u8fd9\u4e2a\u65f6\u5019\uff0c\u4f60\u53ef\u4ee5\u8d28\u95ee\u9762\u8bd5\u5b98\uff0c\u4e3a\u4ec0\u4e48\u8fd9\u4e48\u5947\u602a\uff0c\u8981\u5728\u591a\u7ebf\u7a0b\u7684\u73af\u5883\u4e0b\u4f7f\u7528HashMap\u5462\uff1f\uff1a\uff09<\/p>\n<p>\u70ed\u5fc3\u7684\u8bfb\u8005\u8d21\u732e\u4e86\u66f4\u591a\u7684\u5173\u4e8eHashMap\u7684\u95ee\u9898\uff1a<\/p>\n<ol>\n<li><strong>\u4e3a\u4ec0\u4e48String, Interger\u8fd9\u6837\u7684wrapper\u7c7b\u9002\u5408\u4f5c\u4e3a\u952e\uff1f<\/strong>\u00a0String, Interger\u8fd9\u6837\u7684wrapper\u7c7b\u4f5c\u4e3aHashMap\u7684\u952e\u662f\u518d\u9002\u5408\u4e0d\u8fc7\u4e86\uff0c\u800c\u4e14String\u6700\u4e3a\u5e38\u7528\u3002\u56e0\u4e3aString\u662f\u4e0d\u53ef\u53d8\u7684\uff0c\u4e5f\u662ffinal\u7684\uff0c\u800c\u4e14\u5df2\u7ecf\u91cd\u5199\u4e86equals()\u548chashCode()\u65b9\u6cd5\u4e86\u3002\u5176\u4ed6\u7684wrapper\u7c7b\u4e5f\u6709\u8fd9\u4e2a\u7279\u70b9\u3002\u4e0d\u53ef\u53d8\u6027\u662f\u5fc5\u8981\u7684\uff0c\u56e0\u4e3a\u4e3a\u4e86\u8981\u8ba1\u7b97hashCode()\uff0c\u5c31\u8981\u9632\u6b62\u952e\u503c\u6539\u53d8\uff0c\u5982\u679c\u952e\u503c\u5728\u653e\u5165\u65f6\u548c\u83b7\u53d6\u65f6\u8fd4\u56de\u4e0d\u540c\u7684hashcode\u7684\u8bdd\uff0c\u90a3\u4e48\u5c31\u4e0d\u80fd\u4eceHashMap\u4e2d\u627e\u5230\u4f60\u60f3\u8981\u7684\u5bf9\u8c61\u3002\u4e0d\u53ef\u53d8\u6027\u8fd8\u6709\u5176\u4ed6\u7684\u4f18\u70b9\u5982\u7ebf\u7a0b\u5b89\u5168\u3002\u5982\u679c\u4f60\u53ef\u4ee5\u4ec5\u4ec5\u901a\u8fc7\u5c06\u67d0\u4e2afield\u58f0\u660e\u6210final\u5c31\u80fd\u4fdd\u8bc1hashCode\u662f\u4e0d\u53d8\u7684\uff0c\u90a3\u4e48\u8bf7\u8fd9\u4e48\u505a\u5427\u3002\u56e0\u4e3a\u83b7\u53d6\u5bf9\u8c61\u7684\u65f6\u5019\u8981\u7528\u5230equals()\u548chashCode()\u65b9\u6cd5\uff0c\u90a3\u4e48\u952e\u5bf9\u8c61\u6b63\u786e\u7684\u91cd\u5199\u8fd9\u4e24\u4e2a\u65b9\u6cd5\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u5982\u679c\u4e24\u4e2a\u4e0d\u76f8\u7b49\u7684\u5bf9\u8c61\u8fd4\u56de\u4e0d\u540c\u7684hashcode\u7684\u8bdd\uff0c\u90a3\u4e48\u78b0\u649e\u7684\u51e0\u7387\u5c31\u4f1a\u5c0f\u4e9b\uff0c\u8fd9\u6837\u5c31\u80fd\u63d0\u9ad8HashMap\u7684\u6027\u80fd\u3002<\/li>\n<li><strong>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u81ea\u5b9a\u4e49\u7684\u5bf9\u8c61\u4f5c\u4e3a\u952e\u5417\uff1f<\/strong> \u8fd9\u662f\u524d\u4e00\u4e2a\u95ee\u9898\u7684\u5ef6\u4f38\u3002\u5f53\u7136\u4f60\u53ef\u80fd\u4f7f\u7528\u4efb\u4f55\u5bf9\u8c61\u4f5c\u4e3a\u952e\uff0c\u53ea\u8981\u5b83\u9075\u5b88\u4e86equals()\u548chashCode()\u65b9\u6cd5\u7684\u5b9a\u4e49\u89c4\u5219\uff0c\u5e76\u4e14\u5f53\u5bf9\u8c61\u63d2\u5165\u5230Map\u4e2d\u4e4b\u540e\u5c06\u4e0d\u4f1a\u518d\u6539\u53d8\u4e86\u3002\u5982\u679c\u8fd9\u4e2a\u81ea\u5b9a\u4e49\u5bf9\u8c61\u65f6\u4e0d\u53ef\u53d8\u7684\uff0c\u90a3\u4e48\u5b83\u5df2\u7ecf\u6ee1\u8db3\u4e86\u4f5c\u4e3a\u952e\u7684\u6761\u4ef6\uff0c\u56e0\u4e3a\u5f53\u5b83\u521b\u5efa\u4e4b\u540e\u5c31\u5df2\u7ecf\u4e0d\u80fd\u6539\u53d8\u4e86\u3002<\/li>\n<li><strong>\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528CocurrentHashMap\u6765\u4ee3\u66ffHashtable\u5417\uff1f<\/strong>\u8fd9\u662f\u53e6\u5916\u4e00\u4e2a\u5f88\u70ed\u95e8\u7684\u9762\u8bd5\u9898\uff0c\u56e0\u4e3aConcurrentHashMap\u8d8a\u6765\u8d8a\u591a\u4eba\u7528\u4e86\u3002\u6211\u4eec\u77e5\u9053Hashtable\u662fsynchronized\u7684\uff0c\u4f46\u662fConcurrentHashMap\u540c\u6b65\u6027\u80fd\u66f4\u597d\uff0c\u56e0\u4e3a\u5b83\u4ec5\u4ec5\u6839\u636e\u540c\u6b65\u7ea7\u522b\u5bf9map\u7684\u4e00\u90e8\u5206\u8fdb\u884c\u4e0a\u9501\u3002ConcurrentHashMap\u5f53\u7136\u53ef\u4ee5\u4ee3\u66ffHashTable\uff0c\u4f46\u662fHashTable\u63d0\u4f9b\u66f4\u5f3a\u7684\u7ebf\u7a0b\u5b89\u5168\u6027\u3002\u770b\u770b<a href=\"http:\/\/javarevisited.blogspot.sg\/2011\/04\/difference-between-concurrenthashmap.html\">\u8fd9\u7bc7\u535a\u5ba2<\/a>\u67e5\u770bHashtable\u548cConcurrentHashMap\u7684\u533a\u522b\u3002<\/li>\n<\/ol>\n<p>\u6211\u4e2a\u4eba\u5f88\u559c\u6b22\u8fd9\u4e2a\u95ee\u9898\uff0c\u56e0\u4e3a\u8fd9\u4e2a\u95ee\u9898\u7684\u6df1\u5ea6\u548c\u5e7f\u5ea6\uff0c\u4e5f\u4e0d\u76f4\u63a5\u7684\u6d89\u53ca\u5230\u4e0d\u540c\u7684\u6982\u5ff5\u3002\u8ba9\u6211\u4eec\u518d\u6765\u770b\u770b\u8fd9\u4e9b\u95ee\u9898\u8bbe\u8ba1\u54ea\u4e9b\u77e5\u8bc6\u70b9\uff1a<\/p>\n<ul>\n<li>hashing\u7684\u6982\u5ff5<\/li>\n<li>HashMap\u4e2d\u89e3\u51b3\u78b0\u649e\u7684\u65b9\u6cd5<\/li>\n<li>equals()\u548chashCode()\u7684\u5e94\u7528\uff0c\u4ee5\u53ca\u5b83\u4eec\u5728HashMap\u4e2d\u7684\u91cd\u8981\u6027<\/li>\n<li>\u4e0d\u53ef\u53d8\u5bf9\u8c61\u7684\u597d\u5904<\/li>\n<li>HashMap\u591a\u7ebf\u7a0b\u7684\u6761\u4ef6\u7ade\u4e89<\/li>\n<li>\u91cd\u65b0\u8c03\u6574HashMap\u7684\u5927\u5c0f<\/li>\n<\/ul>\n<p>\u6ce8:\u54c8\u5e0c\u8868:\u00a0\u5728\u5bf9\u8c61\u7684\u5b58\u50a8\u4f4d\u7f6e\u548c\u5bf9\u8c61\u7684\u5173\u952e\u5c5e\u6027\uff08\u8bbe\u4e3a k\uff09\u4e4b\u95f4\u5efa\u7acb\u4e00\u4e2a\u7279\u5b9a\u7684\u5bf9\u5e94\u5173\u7cfb\uff08\u8bbe\u4e3a f\uff09\uff0c\u4f7f\u6bcf\u4e2a\u5bf9\u8c61\u4e0e\u4e00\u4e2a\u552f\u4e00\u7684\u5b58\u50a8\u4f4d\u7f6e\u76f8\u5bf9\u5e94\u3002\u5728\u67e5\u627e\u65f6\uff0c\u53ea\u8981\u6839\u636e\u5f85\u67e5\u5bf9\u8c61\u7684\u5173\u952e\u5c5e\u6027 k \u8ba1\u7b97f(k)\u7684\u503c\u5373\u53ef\u3002\u5982\u679c\u6b64\u5bf9\u8c61\u5728\u96c6\u5408\u4e2d\uff0c\u5219\u5fc5\u5b9a\u5728\u5b58\u50a8\u4f4d\u7f6e f(k)\u4e0a\uff0c\u79f0\u8fd9\u79cd\u5bf9\u5e94\u5173\u7cfb f \u4e3a\u54c8\u5e0c\uff08hash\uff09\u65b9\u6cd5\uff0c\u6309\u7167\u8fd9\u79cd\u601d\u60f3\u5efa\u7acb\u7684\u8868\u4e3a\u54c8\u5e0c\u8868\u3002<\/p>\n<h3><a class=\"external\" href=\"https:\/\/github.com\/stephanietang\/ImportNew\/blob\/master\/Java\/How%20HashMap%20works%20in%20Java.md#%E6%80%BB%E7%BB%93\" target=\"_blank\" rel=\"nofollow\" name=\"%E6%80%BB%E7%BB%93\"><\/a>\u603b\u7ed3<\/h3>\n<h4><a href=\"https:\/\/github.com\/stephanietang\/ImportNew\/blob\/master\/Java\/How%20HashMap%20works%20in%20Java.md#hashmap%E7%9A%84%E5%B7%A5%E4%BD%9C%E5%8E%9F%E7%90%86-1\" name=\"hashmap%E7%9A%84%E5%B7%A5%E4%BD%9C%E5%8E%9F%E7%90%86-1\"><\/a>HashMap\u7684\u5de5\u4f5c\u539f\u7406<\/h4>\n<p>\u5bf9\u4e8e HashMap \u53ca\u5176\u5b50\u7c7b\u800c\u8a00\uff0c\u5b83\u4eec\u91c7\u7528 Hash \u7b97\u6cd5\u6765\u51b3\u5b9a\u96c6\u5408\u4e2d\u5143\u7d20\u7684\u5b58\u50a8\u4f4d\u7f6e\u3002\u5f53\u7cfb\u7edf\u5f00\u59cb\u521d\u59cb\u5316 HashMap \u65f6\uff0c\u7cfb\u7edf\u4f1a\u521b\u5efa\u4e00\u4e2a\u957f\u5ea6\u4e3a capacity \u7684 Entry \u6570\u7ec4\uff0c\u8fd9\u4e2a\u6570\u7ec4\u91cc\u53ef\u4ee5\u5b58\u50a8\u5143\u7d20\u7684\u4f4d\u7f6e\u88ab\u79f0\u4e3a\u201c\u6876\uff08bucket\uff09\u201d\uff0c\u6bcf\u4e2a bucket \u90fd\u6709\u5176\u6307\u5b9a\u7d22\u5f15\uff0c\u7cfb\u7edf\u53ef\u4ee5\u6839\u636e\u5176\u7d22\u5f15\u5feb\u901f\u8bbf\u95ee\u8be5 bucket \u91cc\u5b58\u50a8\u7684\u5143\u7d20\u3002<\/p>\n<p>\u65e0\u8bba\u4f55\u65f6\uff0cHashMap \u7684\u6bcf\u4e2a\u201c\u6876\u201d\u53ea\u5b58\u50a8\u4e00\u4e2a\u5143\u7d20\uff08\u4e5f\u5c31\u662f\u4e00\u4e2a Entry\uff09\uff0c\u7531\u4e8e Entry \u5bf9\u8c61\u53ef\u4ee5\u5305\u542b\u4e00\u4e2a\u5f15\u7528\u53d8\u91cf\uff08\u5c31\u662f Entry \u6784\u9020\u5668\u7684\u7684\u6700\u540e\u4e00\u4e2a\u53c2\u6570\uff09\u7528\u4e8e\u6307\u5411\u4e0b\u4e00\u4e2a Entry\uff0c\u56e0\u6b64\u53ef\u80fd\u51fa\u73b0\u7684\u60c5\u51b5\u662f\uff1aHashMap \u7684 bucket \u4e2d\u53ea\u6709\u4e00\u4e2a Entry\uff0c\u4f46\u8fd9\u4e2a Entry \u6307\u5411\u53e6\u4e00\u4e2a Entry \u2014\u2014\u8fd9\u5c31\u5f62\u6210\u4e86\u4e00\u4e2a Entry \u94fe\u3002<\/p>\n<p><span style=\"color: #993366;\">HashMap\u57fa\u4e8ehashing\u539f\u7406\uff0c\u6211\u4eec\u901a\u8fc7put()\u548cget()\u65b9\u6cd5\u50a8\u5b58\u548c\u83b7\u53d6\u5bf9\u8c61\u3002\u5f53\u6211\u4eec\u5c06\u952e\u503c\u5bf9\u4f20\u9012\u7ed9put()\u65b9\u6cd5\u65f6\uff0c\u5b83\u8c03\u7528\u952e\u5bf9\u8c61\u7684hashCode()\u65b9\u6cd5\u6765\u8ba1\u7b97hashcode\uff0c\u8ba9\u540e\u627e\u5230bucket\u4f4d\u7f6e\u6765\u50a8\u5b58\u503c\u5bf9\u8c61\u3002\u5f53\u83b7\u53d6\u5bf9\u8c61\u65f6\uff0c\u5148\u627e\u5230bucket\u4f4d\u7f6e,\u7136\u540e\u901a\u8fc7\u952e\u5bf9\u8c61\u7684equals()\u65b9\u6cd5\u627e\u5230\u6b63\u786e\u7684\u952e\u503c\u5bf9\uff0c\u7136\u540e\u8fd4\u56de\u503c\u5bf9\u8c61\u3002HashMap\u4f7f\u7528\u94fe\u8868\u6765\u89e3\u51b3\u78b0\u649e\u95ee\u9898\uff0c\u5f53\u53d1\u751f\u78b0\u649e\u4e86\uff0c\u5bf9\u8c61\u5c06\u4f1a\u50a8\u5b58\u5728\u94fe\u8868\u7684\u4e0b\u4e00\u4e2a\u8282\u70b9\u4e2d\u3002 HashMap\u5728\u6bcf\u4e2a\u94fe\u8868\u8282\u70b9\u4e2d\u50a8\u5b58\u952e\u503c\u5bf9\u5bf9\u8c61\u3002<\/span><\/p>\n<p><span style=\"color: #993366;\">\u5f53\u4e24\u4e2a\u4e0d\u540c\u7684\u952e\u5bf9\u8c61\u7684hashcode\u76f8\u540c\u65f6\u4f1a\u53d1\u751f\u4ec0\u4e48\uff1f \u5b83\u4eec\u4f1a\u50a8\u5b58\u5728\u540c\u4e00\u4e2abucket\u4f4d\u7f6e\u7684\u94fe\u8868\u4e2d\u3002\u952e\u5bf9\u8c61\u7684equals()\u65b9\u6cd5\u7528\u6765\u627e\u5230\u952e\u503c\u5bf9\u3002<\/span><\/p>\n<p>\u56e0\u4e3aHashMap\u7684\u597d\u5904\u975e\u5e38\u591a\uff0c\u6211\u66fe\u7ecf\u5728\u7535\u5b50\u5546\u52a1\u7684\u5e94\u7528\u4e2d\u4f7f\u7528HashMap\u4f5c\u4e3a\u7f13\u5b58\u3002\u56e0\u4e3a\u91d1\u878d\u9886\u57df\u975e\u5e38\u591a\u7684\u8fd0\u7528Java\uff0c\u4e5f\u51fa\u4e8e\u6027\u80fd\u7684\u8003\u8651\uff0c\u6211\u4eec\u4f1a\u7ecf\u5e38\u7528\u5230HashMap\u548cConcurrentHashMap\u3002<\/p>\n<p><a href=\"https:\/\/ai.zhousir.top\/wp-content\/uploads\/2016\/10\/hashmap.jpg\" rel=\"fancybox\"><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-1739\" src=\"https:\/\/ai.zhousir.top\/wp-content\/uploads\/2016\/10\/hashmap.jpg\" alt=\"hashmap\" width=\"590\" height=\"627\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>\u539f\u6587\u94fe\u63a5\uff1a <a class=\"external\" href=\"http:\/\/javarevisited.blogspot.hk\/2011\/02\/how-hashmap-works-in-java.html\" target=\"_blank\" rel=\"nofollow\">Javarevisited<\/a> \u7ffb\u8bd1\uff1a <a href=\"http:\/\/www.importnew.com\/\">ImportNew.com <\/a>&#8211; <a href=\"http:\/\/www.importnew.com\/author\/tangxiaojuan\">\u5510\u5c0f\u5a1f<\/a><br \/>\n\u8bd1\u6587\u94fe\u63a5\uff1a <a href=\"http:\/\/www.importnew.com\/7099.html\">http:\/\/www.importnew.com\/7099.html<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5148\u6765\u4e9b\u7b80\u5355\u7684\u95ee\u9898 \u201c\u4f60\u7528\u8fc7HashMap\u5417\uff1f\u201d \u201c\u4ec0\u4e48\u662fHashMap\uff1f\u4f60\u4e3a\u4ec0\u4e48\u7528\u5230\u5b83\uff1f\u201d \u51e0\u4e4e\u6bcf\u4e2a\u4eba\u90fd\u4f1a\u56de\u7b54 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